Abstract:
A magnetic recording medium whose magnetic layer formed on a base comprises a magnetic powder and a binder which contains a tertiary amine and uses 1,4-cyclohexanedimethanol as a chain extender. The magnetic powder is preferably of CrO.sub.2. The medium is made by mixing and dispersing the magnetic powder in a binder which consists of a reaction product of (A) a polyester which is a reaction product of a diol selected from among ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentadiol, and 1,6-hexanediol, and adipic acid, (B) a chain extender consisting of 1,4-cyclohexanedimethanol, (C) an aliphatic or aromatic diisocyanate in an amount substantially equal to the combined molar amount of the polyester and the chain extender, and (D) a tertiary amine, and applying the resulting magnetic coating material to a base.
Abstract:
In a magnetic recording medium having a magnetic recording coat formed on one side of a base and a back coat on the other side, the back coat consists of a dispersion in a binder of an inorgainc pigment powder having an average particle diameter of 0.2 to 0.5 .mu.m and a Mohs hardness of not greater than 6. The binder consists of a specific copolymer, a rubber-like binder, and a polyisocyanate ingredient. The copolymer consists of vinyl chloride, a vinyl alkyl carboxylate, a monomer copolymerizable with vinyl chloride, and a saponified vinyl alkyl carboxylate and has an OH/CH absorption ratio as determined from its infrared absorption spectrum in the range of 0.2 to 0.7.
Abstract:
A magnetic recording medium comprises a substrate coated with a magnetic layer comprising a magnetic powder and a binder comprising an urethane resin or a polyester and a vinyl chloride type copolymer of vinyl chloride-vinyl acetate-vinyl alcohol copolymer, vinyl chloride-vinyl acetate-maleic acid copolymer or vinyl chloride-vinylidene chloride copolymer having a polymerization degree of up to 300.
Abstract:
A magnetic recording medium consisting of a base coated with magnetic coating material which is a dispersion of magnetic particles using a vinyl chloride-vinyl acetate copolymer and a polyester resin as binder, characterized by the addition of a vinyl chloride-vinyl acetate copolymer containing at least 10% of vinyl alcohol. The use of the last-mentioned copolymer improves the frequency response characteristic as well as the mechanical properties such as the running quality.
Abstract:
A magnetic recording medium comprises a substrate coated with a magnetic layer comprising a magnetic powder and a binder and a rust inhibitor at a ratio of more than 0.1 wt. % based on resins of the binder.
Abstract:
A magnetic recording medium comprises a substrate coated with a magnetic layer wherein a magnetic powder is orientated in a binder and a polyoxyethylenesorbitane higher fatty acid ester surfactant.
Abstract:
A magnetic recording medium comprises a substrate coated with a magnetic coating composition comprising nitrocellulose impregnated with a vinyl chloride-vinyl acetate-vinyl alcohol copolymer having a content of vinyl alcohol component of 8 wt. % or more, a magnetic powder, a solvent, and a thermal crosslinking agent.
Abstract:
Polyoxymethylene articles having a surface printable with an ultraviolet-curing ink are obtained by molding a polyoxymethylene and treating the molded article by ultraviolet irradiation, corona discharge, or electron-beam radiation until the surface has an X-ray photoelectron spectrum in which the ratio of the �C--O!.sub.n bond peak at 302 eV to the C--C bond peak at 305 eV, i.e., the �C--O!.sub.n bond peak/C--C bond peak ratio, is at least 2.5.